/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

/*
 *  RFC 1321 compliant MD5 implementation
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
/*
 *  The MD5 algorithm was designed by Ron Rivest in 1991.
 *
 *  http://www.ietf.org/rfc/rfc1321.txt
 */

#include "tls/config.h"

#if defined(MBEDTLS_MD5_C)

#include "tls/md5.h"

#include <string.h>

#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "tls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif							/* MBEDTLS_PLATFORM_C */
#endif							/* MBEDTLS_SELF_TEST */

#if !defined(MBEDTLS_MD5_ALT)

/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize(void *v, size_t n)
{
	volatile unsigned char *p = v;
	while (n--) {
		*p++ = 0;
	}
}

/*
 * 32-bit integer manipulation macros (little endian)
 */
#ifndef GET_UINT32_LE
#define GET_UINT32_LE(n, b, i)			\
{										\
	(n)	= ((uint32_t)(b)[(i)])			\
	| ((uint32_t)(b)[(i) + 1] <<  8)	\
	| ((uint32_t)(b)[(i) + 2] << 16)   \
	| ((uint32_t)(b)[(i) + 3] << 24);  \
}
#endif

#ifndef PUT_UINT32_LE
#define PUT_UINT32_LE(n, b, i)								\
{															\
	(b)[(i)] = (unsigned char)(((n)) & 0xFF);			\
	(b)[(i) + 1] = (unsigned char)(((n) >>  8) & 0xFF);	\
	(b)[(i) + 2] = (unsigned char)(((n) >> 16) & 0xFF);	\
	(b)[(i) + 3] = (unsigned char)(((n) >> 24) & 0xFF);	\
}
#endif

void mbedtls_md5_init(mbedtls_md5_context *ctx)
{
	memset(ctx, 0, sizeof(mbedtls_md5_context));
}

void mbedtls_md5_free(mbedtls_md5_context *ctx)
{
	if (ctx == NULL) {
		return;
	}

	mbedtls_zeroize(ctx, sizeof(mbedtls_md5_context));
}

void mbedtls_md5_clone(mbedtls_md5_context *dst, const mbedtls_md5_context *src)
{
	*dst = *src;
}

/*
 * MD5 context setup
 */
void mbedtls_md5_starts(mbedtls_md5_context *ctx)
{
	ctx->total[0] = 0;
	ctx->total[1] = 0;

	ctx->state[0] = 0x67452301;
	ctx->state[1] = 0xEFCDAB89;
	ctx->state[2] = 0x98BADCFE;
	ctx->state[3] = 0x10325476;
}

#if !defined(MBEDTLS_MD5_PROCESS_ALT)
void mbedtls_md5_process(mbedtls_md5_context *ctx, const unsigned char data[64])
{
	uint32_t X[16], A, B, C, D;

	GET_UINT32_LE(X[0], data, 0);
	GET_UINT32_LE(X[1], data, 4);
	GET_UINT32_LE(X[2], data, 8);
	GET_UINT32_LE(X[3], data, 12);
	GET_UINT32_LE(X[4], data, 16);
	GET_UINT32_LE(X[5], data, 20);
	GET_UINT32_LE(X[6], data, 24);
	GET_UINT32_LE(X[7], data, 28);
	GET_UINT32_LE(X[8], data, 32);
	GET_UINT32_LE(X[9], data, 36);
	GET_UINT32_LE(X[10], data, 40);
	GET_UINT32_LE(X[11], data, 44);
	GET_UINT32_LE(X[12], data, 48);
	GET_UINT32_LE(X[13], data, 52);
	GET_UINT32_LE(X[14], data, 56);
	GET_UINT32_LE(X[15], data, 60);

#define S(x, n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))

#define P(a , b, c, d, k, s, t)						\
{                                                   \
	a += F(b, c, d) + X[k] + t; a = S(a, s) + b;       \
}

	A = ctx->state[0];
	B = ctx->state[1];
	C = ctx->state[2];
	D = ctx->state[3];

#define F(x, y, z) (z ^ (x & (y ^ z)))

	P(A, B, C, D, 0, 7, 0xD76AA478);
	P(D, A, B, C, 1, 12, 0xE8C7B756);
	P(C, D, A, B, 2, 17, 0x242070DB);
	P(B, C, D, A, 3, 22, 0xC1BDCEEE);
	P(A, B, C, D, 4, 7, 0xF57C0FAF);
	P(D, A, B, C, 5, 12, 0x4787C62A);
	P(C, D, A, B, 6, 17, 0xA8304613);
	P(B, C, D, A, 7, 22, 0xFD469501);
	P(A, B, C, D, 8, 7, 0x698098D8);
	P(D, A, B, C, 9, 12, 0x8B44F7AF);
	P(C, D, A, B, 10, 17, 0xFFFF5BB1);
	P(B, C, D, A, 11, 22, 0x895CD7BE);
	P(A, B, C, D, 12, 7, 0x6B901122);
	P(D, A, B, C, 13, 12, 0xFD987193);
	P(C, D, A, B, 14, 17, 0xA679438E);
	P(B, C, D, A, 15, 22, 0x49B40821);

#undef F

#define F(x, y, z) (y ^ (z & (x ^ y)))

	P(A, B, C, D, 1, 5, 0xF61E2562);
	P(D, A, B, C, 6, 9, 0xC040B340);
	P(C, D, A, B, 11, 14, 0x265E5A51);
	P(B, C, D, A, 0, 20, 0xE9B6C7AA);
	P(A, B, C, D, 5, 5, 0xD62F105D);
	P(D, A, B, C, 10, 9, 0x02441453);
	P(C, D, A, B, 15, 14, 0xD8A1E681);
	P(B, C, D, A, 4, 20, 0xE7D3FBC8);
	P(A, B, C, D, 9, 5, 0x21E1CDE6);
	P(D, A, B, C, 14, 9, 0xC33707D6);
	P(C, D, A, B, 3, 14, 0xF4D50D87);
	P(B, C, D, A, 8, 20, 0x455A14ED);
	P(A, B, C, D, 13, 5, 0xA9E3E905);
	P(D, A, B, C, 2, 9, 0xFCEFA3F8);
	P(C, D, A, B, 7, 14, 0x676F02D9);
	P(B, C, D, A, 12, 20, 0x8D2A4C8A);

#undef F

#define F(x, y, z) (x ^ y ^ z)

	P(A, B, C, D, 5, 4, 0xFFFA3942);
	P(D, A, B, C, 8, 11, 0x8771F681);
	P(C, D, A, B, 11, 16, 0x6D9D6122);
	P(B, C, D, A, 14, 23, 0xFDE5380C);
	P(A, B, C, D, 1, 4, 0xA4BEEA44);
	P(D, A, B, C, 4, 11, 0x4BDECFA9);
	P(C, D, A, B, 7, 16, 0xF6BB4B60);
	P(B, C, D, A, 10, 23, 0xBEBFBC70);
	P(A, B, C, D, 13, 4, 0x289B7EC6);
	P(D, A, B, C, 0, 11, 0xEAA127FA);
	P(C, D, A, B, 3, 16, 0xD4EF3085);
	P(B, C, D, A, 6, 23, 0x04881D05);
	P(A, B, C, D, 9, 4, 0xD9D4D039);
	P(D, A, B, C, 12, 11, 0xE6DB99E5);
	P(C, D, A, B, 15, 16, 0x1FA27CF8);
	P(B, C, D, A, 2, 23, 0xC4AC5665);

#undef F

#define F(x, y, z) (y ^ (x | ~z))

	P(A, B, C, D, 0, 6, 0xF4292244);
	P(D, A, B, C, 7, 10, 0x432AFF97);
	P(C, D, A, B, 14, 15, 0xAB9423A7);
	P(B, C, D, A, 5, 21, 0xFC93A039);
	P(A, B, C, D, 12, 6, 0x655B59C3);
	P(D, A, B, C, 3, 10, 0x8F0CCC92);
	P(C, D, A, B, 10, 15, 0xFFEFF47D);
	P(B, C, D, A, 1, 21, 0x85845DD1);
	P(A, B, C, D, 8, 6, 0x6FA87E4F);
	P(D, A, B, C, 15, 10, 0xFE2CE6E0);
	P(C, D, A, B, 6, 15, 0xA3014314);
	P(B, C, D, A, 13, 21, 0x4E0811A1);
	P(A, B, C, D, 4, 6, 0xF7537E82);
	P(D, A, B, C, 11, 10, 0xBD3AF235);
	P(C, D, A, B, 2, 15, 0x2AD7D2BB);
	P(B, C, D, A, 9, 21, 0xEB86D391);

#undef F

	ctx->state[0] += A;
	ctx->state[1] += B;
	ctx->state[2] += C;
	ctx->state[3] += D;
}
#endif							/* !MBEDTLS_MD5_PROCESS_ALT */

/*
 * MD5 process buffer
 */
void mbedtls_md5_update(mbedtls_md5_context *ctx, const unsigned char *input, size_t ilen)
{
	size_t fill;
	uint32_t left;

	if (ilen == 0) {
		return;
	}

	left = ctx->total[0] & 0x3F;
	fill = 64 - left;

	ctx->total[0] += (uint32_t)ilen;
	ctx->total[0] &= 0xFFFFFFFF;

	if (ctx->total[0] < (uint32_t)ilen) {
		ctx->total[1]++;
	}

	if (left && ilen >= fill) {
		memcpy((void *)(ctx->buffer + left), input, fill);
		mbedtls_md5_process(ctx, ctx->buffer);
		input += fill;
		ilen -= fill;
		left = 0;
	}

	while (ilen >= 64) {
		mbedtls_md5_process(ctx, input);
		input += 64;
		ilen -= 64;
	}

	if (ilen > 0) {
		memcpy((void *)(ctx->buffer + left), input, ilen);
	}
}

static const unsigned char md5_padding[64] = {
	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

/*
 * MD5 final digest
 */
void mbedtls_md5_finish(mbedtls_md5_context *ctx, unsigned char output[16])
{
	uint32_t last, padn;
	uint32_t high, low;
	unsigned char msglen[8];

	high = (ctx->total[0] >> 29)
		   | (ctx->total[1] << 3);
	low = (ctx->total[0] << 3);

	PUT_UINT32_LE(low, msglen, 0);
	PUT_UINT32_LE(high, msglen, 4);

	last = ctx->total[0] & 0x3F;
	padn = (last < 56) ? (56 - last) : (120 - last);

	mbedtls_md5_update(ctx, md5_padding, padn);
	mbedtls_md5_update(ctx, msglen, 8);

	PUT_UINT32_LE(ctx->state[0], output, 0);
	PUT_UINT32_LE(ctx->state[1], output, 4);
	PUT_UINT32_LE(ctx->state[2], output, 8);
	PUT_UINT32_LE(ctx->state[3], output, 12);
}

#endif							/* !MBEDTLS_MD5_ALT */

/*
 * output = MD5( input buffer)
 */
void mbedtls_md5(const unsigned char *input, size_t ilen, unsigned char output[16])
{
	mbedtls_md5_context ctx;

	mbedtls_md5_init(&ctx);
	mbedtls_md5_starts(&ctx);
	mbedtls_md5_update(&ctx, input, ilen);
	mbedtls_md5_finish(&ctx, output);
	mbedtls_md5_free(&ctx);
}

#if defined(MBEDTLS_SELF_TEST)
/*
 * RFC 1321 test vectors
 */
static const unsigned char md5_test_buf[7][81] = {
	{""},
	{"a"},
	{"abc"},
	{"message digest"},
	{"abcdefghijklmnopqrstuvwxyz"},
	{"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"},
	{"12345678901234567890123456789012345678901234567890123456789012" "345678901234567890"}
};

static const int md5_test_buflen[7] = {
	0, 1, 3, 14, 26, 62, 80
};

static const unsigned char md5_test_sum[7][16] = {
	{
		0xD4, 0x1D, 0x8C, 0xD9, 0x8F, 0x00, 0xB2, 0x04,
		0xE9, 0x80, 0x09, 0x98, 0xEC, 0xF8, 0x42, 0x7E
	},
	{
		0x0C, 0xC1, 0x75, 0xB9, 0xC0, 0xF1, 0xB6, 0xA8,
		0x31, 0xC3, 0x99, 0xE2, 0x69, 0x77, 0x26, 0x61
	},
	{
		0x90, 0x01, 0x50, 0x98, 0x3C, 0xD2, 0x4F, 0xB0,
		0xD6, 0x96, 0x3F, 0x7D, 0x28, 0xE1, 0x7F, 0x72
	},
	{
		0xF9, 0x6B, 0x69, 0x7D, 0x7C, 0xB7, 0x93, 0x8D,
		0x52, 0x5A, 0x2F, 0x31, 0xAA, 0xF1, 0x61, 0xD0
	},
	{
		0xC3, 0xFC, 0xD3, 0xD7, 0x61, 0x92, 0xE4, 0x00,
		0x7D, 0xFB, 0x49, 0x6C, 0xCA, 0x67, 0xE1, 0x3B
	},
	{
		0xD1, 0x74, 0xAB, 0x98, 0xD2, 0x77, 0xD9, 0xF5,
		0xA5, 0x61, 0x1C, 0x2C, 0x9F, 0x41, 0x9D, 0x9F
	},
	{
		0x57, 0xED, 0xF4, 0xA2, 0x2B, 0xE3, 0xC9, 0x55,
		0xAC, 0x49, 0xDA, 0x2E, 0x21, 0x07, 0xB6, 0x7A
	}
};

/*
 * Checkup routine
 */
int mbedtls_md5_self_test(int verbose)
{
	int i;
	unsigned char md5sum[16];

	for (i = 0; i < 7; i++) {
		if (verbose != 0) {
			mbedtls_printf("  MD5 test #%d: ", i + 1);
		}

		mbedtls_md5(md5_test_buf[i], md5_test_buflen[i], md5sum);

		if (memcmp(md5sum, md5_test_sum[i], 16) != 0) {
			if (verbose != 0) {
				mbedtls_printf("failed\n");
			}

			return (1);
		}

		if (verbose != 0) {
			mbedtls_printf("passed\n");
		}
	}

	if (verbose != 0) {
		mbedtls_printf("\n");
	}

	return (0);
}

#endif							/* MBEDTLS_SELF_TEST */

#endif							/* MBEDTLS_MD5_C */
